Aeroplane-rib.



W. C. ROBINSON.

AEROPLANE RIB.

APPLICATION FILED MAR. 27. 1916.

jlfilfififiu Patented Feb. 6, 1917.

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Specification of Letters Patent.

Patented Feb. 6, 1121?.

Application filed March 27, 1916. Serial No. 87,118.

To all whom it may concern:

Be it known that I, WILLIAM C. ROBIN- soN, a citizen of the United States, and resident of Grinnell, in the county of Pow'eshiek and State of Iowa, have invented a certain new and useful Aeroplane-Rib, of which the following is a specification.

The object of my invention is to provide a rib of simple, durable and inexpensive construction, especially designed for use in aeroplanes, and containing a maximum of strength and rigidity with a. minimum of weight.

A further object is to provide a rib of this kind in which the various parts are firmly and immovably held together and do not depend to a great extent on glue, nails or other fastening means for holding them together, so that when in use the various twisting strains to which these ribs are subjected will not tend to separate the parts thereof by loosening fastening means such as nails, and also so that the various weather conditions to which these ribs are often subjected will not tend to permit the parts to be separated on account of their deteriorating action on glue or the like.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

Figure 1 shows a side elevation of an aeroplane rib embodying my invention.

Fig. 2 shows a transverse, sectional view through the upper longitudinal rib memher before being shaped. The dotted lines in said figure indicate the parts thereof that are removed in perfecting the upper longitudinal rib member.

Fig. 3 shows an enlarged, sectional view on the line 33 of Fig. 1, and

Fig. 4 shows an enlarged side view of part of a completed rib embodying my invention, taken at a point through which one of the transverse beams is extended when in use.

Referring to the accompanying drawings, it'will be seen that the rib is composed of upper and lower longitudinal members and a series of upright supports for connecting the upper and lower longitudinal members.

The two longitudinal rib members are each formed of a single piece of material,

preferably wood. The top longjtudinal member has a flat top portion 10 and an integral downwardly extending rib 11 centrally arranged, thus forming a substantially "IF-shaped member in cross section, as shown in Fig. 3. The lower longitudinal rib member has a flat bottom portion 12 and an upwardly extending rib 13, forming an inverted T-shaped member. These two longitudinal rib members are at their central portions spaced apart a few inches, and at their end portions they are brought together and secured in anyv desirable way, the ribs 11 and 13 being tapered off at the end portions to permit the flat parts 10 and 12 to come together, as shown in Fig. 1.

Throughout the body portion of my improved rib I have provided a series of upright struts or bracing members, each of which is composed of a substantially rectangular body portion 14, preferably of wood, and having slots at its upper and lower ends to receive the rods 11 and 13, as clearly shown in Fig. 3.

At points spaced apart from the front and from the rear of the rib, I provide openings to receive the transverse beams 15. These beams are of the kind ordinarily provided for connecting together a number of these ribs for forming an aeroplane wing. At the points where these beams 13 enter the ribs, the flanges 11 and 13 are cut away and two of the struts 14 are placed close together on opposite sides of the opening for receiving said beams. In order to connect the longi tudinal rib members and the struts, I preferably employ small tacks or nails 16, driven through the end portions of the struts and through the ribs 11 and 13, as illustrated in Fig. 4. a

In constructing the longitudinal members, I preferably employ a piece of wood substantially rectangular in cross section, and then cut away portions thereof, as indicated by dotted lines in Fig. 2, in order to form the T-shaped longitudinal rib member. The makes a member of minimum weight with a maximum of strength, and there is no 'strips very small in cross section.

At the point where the transverse beams 15 are extended through the ribs, the flanges 11 are cut away, as shown in Fig; 4:, but the transverse beams themselves may be firmly connected to the 'top and bottom members 10 and 12, thereby making this part of the rib when combined with the beams, as strong, at least, as any of the other parts.

In practical use it is obvious that these ribs may be constructed very cheaply because the wood or other material from which the ribs are constructed, may be made of more the Work of forming the upper and lower longitudinal members may be cheaply done by machinery and little or no hand work need be employed Furthermore, the struts can be readily and quickly placed in position and tacked or nailed, thus completing the rib.

My improved rib construction is very superior to such a structure as, for instance, one in which the flat top and bottom members 10 and 12 are connected to separate rib pieces 11 and 13, because said ribs are necessarily very thin and cannot be connected to the flat top and bottom members either by nails or glue in such a manner as to produce anything like as great strength as can be obtained by having the T-shaped member forlmed complete of a single piece of mater1a In use these ribs are subjected to such strains as tend to move the upper and lower longitudinal rib members both laterally and up and down relative to each other, but there is almost no tendency to move the Furtherstruts forwardly or rearwardly. In'my improved construction the only oflice or function of the tacks or nails 16 is to hold the struts against movement forwardly or rearwardly. Hence so far as the strains to which these ribs are subjected is concerned, the construction of the upper and lower rib members and the struts when assembled, as shown, provides all of the strength necessary for resisting the strains to which these ribs are ordinarily subjected.

I claim as my invention:

1. An improved aeroplane rib comprising an upper longitudinal member substantially T-shaped in cross section, a lower longitudinal rib member substantially inverted T- shaped in. cross section, each of said rib members being formed of a single piece of material, and a series of struts slotted at their ends to receive the flanges of the longitudinal rib members, for the purposes stated.

WILLIAM C. ROBINSON. 

